This section describes features that are supported by SIP Proxy.
SIP Proxy is responsible for proxying SIP messages from external SIP user agents to the appropriate SIP Server. It is the responsibility of each external user agent to choose a SIP Proxy instance when sending a SIP message. Typically a deployment should have an overall configuration resulting in load balancing across the SIP Proxy instances.
Active Out-of-Service Detection
Each SIP Proxy instance pings each primary SIP Server using an OPTIONS message. If the primary SIP Server does not respond during a configured timeout, SIP Proxy starts to ping the backup SIP Server. If the backup SIP Server responds, the backup SIP Server address will be used as a destination for calls. If both the primary and backup SIP Server instances do not respond, SIP Proxy will mark this SIP Server HA pair as out-of-service and will not use it for calls; however, SIP Proxy will continue pinging them.
Related configuration options:
SIP Proxy has the ability to control and restrict a dialog (incoming INVITE messages) rate. This feature is enabled by the overload-ctrl-dialog-rate configuration option. When the overload is detected, SIP Proxy rejects new INVITE requests by generating a 503 Service Unavailable error message.
SIP Address Binding
SIP Proxy uses the sip-address configuration option to identify on which network interface it should bind the SIP port. If this option is not set, SIP Proxy binds the SIP port on all network interfaces.
SIP Proxy can inform about errors and problems through:
- SCI Alarms
- HTTP Server interface
The following is the list of SIP Proxy log messages of level Standard:
|Log Event ID||Text||Description|
|40000||SPR_OWN_PROXY_ADDR_NOT_FOUND||Initialization failed, proxy address (host:port) is not found in the list|
|40001||SPR_SIPS_HA_PAIR_UNAVAILABLE||SIP Server HA pair (primary host:port) is unavailable|
|40002||SPR_OTHER_PROXY_INSTANCE_DISCONNECTED||SIP Proxy instance is disconnected|
|40003||SPR_ERROR_READING_CONFIG_DATA||Error while reading configuration data|
|40004||SPR_PROXY_INITIALIZED||SIP Proxy has initialized successfully|
|40005||SPR_HOST_NOT_RESOLVED||Cannot resolve SIP Proxy host|
|40006||SPR_SIP_LISTENER_CANNOT_START||Cannot start SIP listener|
|40007||PR_MGMT_LISTENER_CANNOT_START||Cannot start Mgmt listener|
- Loop-detection check mechanism is not supported in this release of SIP Proxy.
- Strict routing is not supported.